The end of an era
by PointlessKnife
Summary: He found it so funny, when the book fell open and nothing happened, no explosion, no fire and no E.N.D. If only he had seen though his tears of laughter and seen that the mage beside him wasn't laughing.
1. The book opens

**A/N Hi guys, me again with another E.N.D one shot. Again, I don't own Fairy Tail and if I did the book of E.N.D would've opened by now. Oh, wait, that's this story. Hope you enjoy!**

It had been two months since the battle with Tartaros, since the demons had been driven back by Fairy Tail. Two months since the book of E.N.D had opened and nothing happened. Gray had burst into frantic laughter at the sight of the book lying motionless, blank pages blowing in the wind, and Mard Geer's horrified expression. Gray was too busy laughing that he didn't see the look on Natsu's face. Or see Mard Geer's face light up in a smirk.

"Hah, your plan failed, what are you going to do now?" Gray sneered.

"It didn't necessarily fail, it could mean that E.N.D reincarnated further away than the plan accounted for. Now that book is open E.N.D _is_ back. Our plan didn't fail, you pathetic human." Mard Geer snarled.

"Natsu, are you okay? You'd normally be rubbing this in that guy's face." Gray asked suddenly.

"Yeah, I just... That book gave of a really nasty vibe just then." Natsu gasped.

"Good." Gray muttered, looking away.

"What, you were worried?" Natsu scoffed.

"No." Gray denied quickly. "Look, lets just focus on kicking this guy into The Grand Magic world."

"Wasn't that the thing that the thing the creeps who attacked us in the S-Class exams were after?" Natsu asked curiously.

"Yeah." Gray said, suprised. "Are you sure you're okay, Flame Brain? You're being intelligent."

"What's that supposed to mean, Stripper?" Natsu growled.

"Look, let's get rid of this guy then talk about your stupidity."

"Whatever."

Mard Geer laughed, smoothly changing into his demon form again. "So, you decided to continue fighting?"

"Yeah," Natsu snarled. "'Cause we're Fairy Tail."

"And we'll never give up!" Gray yelled.

Mard Geer dodged both of their attacks and sent at him and waved a hand, causing vines to burst from the ground and lash out at the two boys.

Natsu and Gray leapt backwards in opposite directions. Gray started freezing the vines with his Ice Devil powers while Natsu charged at Mard Geer, fists on fire.

"You know," Mard Geer hissed in Natsu's ear as he ducked under the blows. "I'm suprised _you_ continued to fight."

"Shut up." Natsu said quietly, sending a vicious punch straight towards the demon's face.

"E.N.D is a mere human, that in itself was suprising." he whispered so Gray couldn't hear. "But the fact he would fight against us. This is getting interesting."

"Shut up!" Natsu roared, the flames on his hands burning brighter.

"You could kill me at any point, just use your curse powers." he taunted.

Gray sent an ice arrow at Mard Geer's head. "You forgot there are two of us here, Pay more attention to what you're doing, demon scum."

Mard Geer grinned. "So that's why." he laughed. He opened his mouth to say something, but he was attacked by Gray.

"You two." Mard Geer spat. "Are far more trouble than you're worth."

Hu put his hand out in front of him. "Go to purgatory."

A dark supstance was rolling in thick waves over the rocky ground. "What is this?" Gray asked. "Fog?"

"Gah, no. I can't move." Natsu snarled through gritted teeth. He glared at Mard Geer, seeing the challenge that was laid out before him. He could break the curse using his own demonic powers but it would mean Gray would see.

Mard Geer looked on, gaze passive. He wondered why E.N.D wouldn't use his curse to destroy him. Was keeping it a secret really that important?

"Memento Mori." he finished, looking at the thick carpet of ash that now covered the ground.

"It appears..." He trailed off when he spotted movement.

Gray's purple eye glowed with a fierce hatred as he glared at Mard Geer. Mard Geer noted the half demonic transformation with intrest but his eyes were drawn to the sinister flames that were fading off Natsu's hands.

"Stupid Ice Devil Slayer getting in my way. E.N.D would've-" Mard Geer was cut off. In his loathing of the human he took his eyes of the two people he was fighting.

Natsu Dragneel was charging at him, coverd in red scales.

His hits hurt, Mard Geer was having effort stopping them. "So this is Dragon Force." he mused thoughtfully.

"Your preferred power, why not just use your curse? Your friend won't see it."

"Zeref-nii will be the only one to see it. I'll never use it unless I have to. I don't need it to end you." Natsu's voice was quiet but it trembled with rage.

The battle ended when Mard Geer was shot in the back by Gray's ice arrow. As he fell to the floor, he croaked "Fufill our... wish."

Natsu's eyes flew open in the dark. He breathed heavily, still panicked by this round of nightmares. He sat up slowly, knowing that his cheeks were covered in dried tears. There was no point going back to sleep, the first rays of dawn were spilling into the sky, casting a rosy half light over the land. He quickly checked on Happy before darting outside. If he was lucky, he had about an hour before Happy woke up and they would leave for the guild.

Thats right. He stayed with the guild instead of going off and training like he originally planned. Every day he put on a brave face and smiled and laughed, comforting his family when they needed it. He needed to stay, after the book and Igneel's death. He couldn't tell anyone about the book, about his past. They'd hate him.

But he couldn't leave either. He was scared of what would happen if he was alone. What kind of monster would he become? Every demon Zeref made had the desire to kill him and Natsu was no exeption. He'd resisted it so far, the urge to go and hunt down the dark wizard and destroy him. It was begining to hurt, he was going to have trouble hiding it.

Happy woke up and they ate fish for breakfast, laughing at small things, like how grumpy Lucy was in the mornings. The Exeed couldn't tell it was a fake laugh, couldn't feel the regret that was burning Natsu from inside.

Once they started walking Happy turned to Natsu, grinning. "Hey, Natsu, let's go annoy Lucy!"

"Maybe we could give it a rest for one day. My head already hurts without being kicked into walls."

"Wah, Natsu are you okay?" Happy cried, frantically checking the dragon slayer. "You have bags under your eyes, are you okay?" he exclaimed, horrified.

"Yeah, I'm fine, just had a little trouble sleeping lately." he laughed sheepishly, cursing himself.

Happy was suddenly serious. "Are they about Igneel? You know you can talk to us at anytime, we're your family."

"Thanks Buddy. I will." Natsu was touched, he so badly wanted to spill everything to his friend. But talking about it could just drag it closer to the surface. Who knows what would happen then? No, he was never going to put his friends in danger.

The guild was fairly empty. Mira waved to him and Gray looked over. He smiled like he always did and took a seat, waiting for Lucy to arrive. He was suprised when Gray sat down opposite him.

"Natsu. Can I talk to you seriously for a second?" He asked, tone hushed so no one could hear.

"Okay."

"Look, I know this is personal to me and all but I need your help."

This was getting weirder and weirder, since when did Gray need _his_ help. Natsu knew already that if it was anything serious that he'd swear to help him but this could turn ugly really fast.

"Go on."

"E.N.D. I need to find and kill him. If I die and he kills me or I'm struggling will you help me fight him?"

No... No, no no. This couldn't be happening. He never did anything other than manage Tartaros as a demon and he never killed anyone. He started to feel sick. What had he done to deserve this? Why did one of his friends have to want him dead?

"S-Sure. Don't worry, I'll... I'll have your back Gray." He lied, feeling his stomach wither with guilt.

"Thanks, Flame Brain." Gray said with a small smile. He walked off to greet Juvia, leaving Natsu to feel awful. He lied, to a friend. He couldn't really kill himself, and he wouldn't kill Gray. Chances were if Zeref died then he would too, and if he was going down then he was as sure as hell bringing Zeref down with him.

Just then a sudden wave of desire washed over him, making him want nothing more than to run, run and find Zeref and complete his purpose. He almost stood up before he fought it off. He saw Lucy and jumped over to her, Happy behind him.

"Hey Luce! Want to go on a mission and fight something?" he asked happily, inside dreading what would come if she were to answer 'yes'. His powers were becoming unstable and his curse would leak into his magic.

"Not really today, can't we just hang around the guild?" she asked.

"Sure thing!" he said feigning sadness. He then brightened up and talked to her rapid fire, making her laugh.

The day was fun, he would talk to his friends, brawl, careful not to use magic and eat the awesome food Mira made. It was ruined by the pangs that his demon side caused but he hid them well enough. Nobody suspected anything.

He offered to walk Lucy back to her apartment, making her laugh fondly. They chatted the whole way back to her apartment, laughing at memories. He never saw what happened next coming. They were at her door, saying goodbye, when she suddenly turned and took his hand, eyes swimming with tears. "Natsu, promise you'll never leave me. Please, I can't lose somebody else. Especially not you."

"Luce..." he said, shocked. He wasn't the only one putting on a brave face, it seemed. "Of course, I'm going to stay by your side whether you like it or not. Promise."

He broke that night. He couldn't stop it any longer and he knew he had to leave before things became worse. Still, he remembered the promises he made, the promises he was about to break. He held it off using the last of his strength and wrote four letters. One to the Guild, one to Happy, One to Gray and the last and the longest to Lucy.

He was gone before dawn.

Happy flew into the guild, crying and clutching scraps of paper to his chest. "Help!" he wailed. "You've got to help, it's Natsu!"

"What?" The Master asked sharply.

"H-Here." Happy sobbed. The Master read the note out loud, voice raising with every word.

"Dear Fairy Tail. I'm sorry, I'm going away. I don't want to but it has to be done. I'm going to fight Zeref and I'm probably not coming back so don't look for me. I'm sorry, you guys were the best family I could have ever asked for. Goodbye, Natsu."

By this point most of the members were staring white faced with shock. "What?" Erza whispered.

"He... Natsu left me a note as well, saying he was sorry and that he didn't want to leave. He left something for Lucy and Gray as well. I haven't read them. Here." Happy cried.

Gary's eyes widened as he read was what in front of him.

 **Yo, Snowflake.**

 **Looks like I won't be able to keep my promise after all, I can't really help you with that now. But if this goes to plan, E.N.D will die along with Zeref. So you'll get to live in peace from now. Look after the guild when I'm gone, I'm going to die in the fight. I'm sorry.**

He didn't realise he started crying until he scrunched up the note and threw it at the wall.

"We've got to stop him!" he snarled. Gajeel nodded and started to sniff the air, searching for Natsu's scent.

Lucy started crying harder as she finished what she'd read. "No." she whispered. She slipped the note into her pocket.

"We have to go after him and bring him back. He can't die... He- He can't leave me alone. He promised."

"Two months. That's very impressive, most demons don't last two minutes and a certain individual lasted two weeks. I'm sorry about all this Natsu, you know. I really am, I just can't go on in this world. Not after 400 years all alone." Zeref said, crying silently.

"Don't cry, Zeref. This was bound to happen sooner or later. You can finally rest now, I'll help you." Natsu's voice was quiet, so unlike his.

"Thank you."

Natsu's body started to glow as he used his demon form.

They decided to use the Magical Vehicles, with Laxus using the SE plug for speed. Inside the car, Makarov, Erza, Lucy, Gray, Wendy, Happy and Carla were having a serious talk.

"You need to tell us what was in your letters, you three. We can't go into this unprepared."

Happy sighed. "Just that this wasn't my fault and that he was sorry."

Gray looked at the floor. "He said he couldn't keep the promise he made me and to look after the guild once he was gone."

Lucy hadn't spoken since she finished her letter. "What was the promise he made you?" She asked, voice hoarse from crying.

"To, well. Help me kill E.N.D."

Lucy let out a groan. "The _idiot_. Of course he'd promise something like that."

"Lucy." Erza asked. "What did he tell you?"

"I'll read it out."

The Master raised an eyebrow, curious.

"Hey Luce. I know you're not going to like this, after all I just promised never to leave you and I'm going already. I wish I could stay with you, I really do. For you to understand I'll have to start from the begining. Yeah, the book of E.N.D opened when we were fighting Mard Geer. Well, it turns out that E.N.D stands for something. Etherious Natsu Dragneel. So when that book opened I became a demon, sort of. I haven't used that form yet. I remembered everything. The plan was for me to join Tartaros and group up to kill Zeref, but I'm still Natsu Dragneel, a Fairy Tail mage so I ignored all the times Mard Geer tried to get me to use my curse powers and fought him. Well, I nearly used them to stop Memento Mori but Gray got there first. Ever since then I've been fighting off the urge to go and kill my brother. Yes, it was written in my book that I'd kill my brother, the one who saved me. Zeref. At first I thought that I just might make it, get along by resisting it. When the dreams started I began to doubt. Each night was a new terror, something dragged back up from the past. I had to lie to Happy, and that was the first betrayal of many. I had to fake every smile, every laugh. It hurt, almost more than the desire, my duty. I made so many promises I knew I'd never be able to keep. I couldn't stop it and it has began to overwhelm me. I couldn't talk, talking would just drag it over to the surface and make it easier for me to drown in it. So I could merley watch. Sorry, this is all so unlike me. Luce, you kept me tied down, made it possible for me to stay as long as I did. I have to say this once, I can't anymore, I have to leave before it gets worse and I turn into a demon. I love you Lucy. I'm sorry. I wish that this hadn't happened, that I was stronger. Natsu."

Lucy was crying again, tears making the ink run down the page. Gray looked shocked and Wendy had started crying, sniffling quietly, not listening to Carla's hushed comforts. Erza looked horrified but none of this compaired to the heart broken wail Happy let loose.

"I'm such a horrible friend. Natsu was going through all that and I didn't even notice!" he cried.

Master Makarov put a hand on Happy's head. "No, Happy. Natsu, it seems went to great pains to hide this from anyone."

He would have added something else but the car skidded to a halt. "It's not safe to come any further, we'll have to go on foot from here on out." Laxus yelled at them.

They walked through the trees near the cliff, magic at the ready. There was a loud explosion, sending a fierce wind at them. They winced and ran, they braced themselves for whatever lay before them.

Natsu had his back to them, and looked totally different. His arms were covered in black flame markings, horns jutted out of his unruly pink hair, and a pair of black and red dragon wings flared out at his back.

"Can I have a minute Zeref?" he asked, still not looking at them.

"Sure, you'll get the job done either way. You probably need to say goodbye." Zeref replied, smiling slightly.

Natsu turned to them, demonic features dissapearing. "Why did you come?" he asked, voice low. He was battered and bruised. He seemed strained, features contorting.

"You idiot, if you think that we're gonna let you just throw your life away then you've got another thing coming!" Gray yelled.

"You're coming back to Fairy Tail, even if we have to drag you there!" Erza stated.

"Please come back with us, Natsu-san." Wendy pleaded.

"S-Shut up all of you. You're making this harder." Natsu screamed, starting to cry. "This would've been so much easier if you didn't come. I could've done it."

"That's the point, we don't want you to do it." Makarov sighed.

Natsu let loose a cry, a shout of pain and clutched his head. He was trembling with the effort of resisting his curse.

"Don't you see? Like this everyone gets what they wanted. E.N.D gets defeated, just like Gray wanted and with Zeref gone, the dark guilds will tone down and Lucy will never lose anyone again." he sniffed. "You'll all get your happy endings."

"I don't want that, Natsu." Lucy cried. "I want you, damn it! Just come back to us, to me please!"

Natsu blinked, for a second he looked like his old self, he reached out to take Lucy's outstreched hand. He suddenly jerked back with a scream, black markings appeared on his skin, wings ripped from his back and horns appeared on his head.

"Natsu!" Happy yelled, voice containing a mix of shock and horror. The demon had flown at Zeref, claws outstreched and before anyone could react they had torn through Zeref's shoulder. The wound exploded in an erruption of wild scarlet and black fire. Zeref choked back a scream but broke off, smiling.

"You can finally do it, thank you Natsu." he said softly, but in the silence that had followed the attack the group of Fairy Tail mages heard every word.

The demon leapt forwards once again, Zeref didn't even try to resist as the sharp black claws pierced his stomach.

"Thank... You.." he croaked. Natsu blinked as Zeref fell to the floor, his eyes turning from a souless black to their usual onyx. He looked down to the floor and his legs buckled.

"No... Zeref. I didn't mean to, oh God, I lost it." he sobbed, turning back into a human. Lucy rushed forwards with a cry. She ran as fast as she could.

She hugged Natsu tightly. He looked at her and smiled weakly. "Sorry Luce, if I wasn't so weak, maybe... Maybe we could've had... A future together." As he spoke a soft gold light enveloped him and started to break away in small parts. It was slow and Natsu was smiling while he was crying. The rest of the group rushed forwards.

"Natsu..."

He gave a grin, not a fake one like the past few months, but a real beam. The curse had stopped, he was finally free.

"No!" A small female voice yelled. The First Master Mavis stood before them.

"You're not going to die here, Natsu. No one will." She announced. Her body started to glow and the light on Natsu started to die down.

"What are you doing?" he yelled frantically.

"I'm using that magic that makes up the form of my ghost and Lumen Histore to restore your life force."

"No, stop!"

"You Dragneel's really need to work on keeping your promises. He promised that I'd never be alone and now he's gone and left me. I'll be having words with him on the other side." She giggled before she faded.

Natsu hung his head in defeat. "Did I... Hurt any of you?" he asked after a while, voice low and heavy with guilt.

"No, you were about to come back to us then you suddenly lost it and killed Zeref." Makarov said, voice shaking slightly.

"Sorry. God, I'm so useless, I just caused two deaths and it isn't even noon." he sobbed. Lucy hugged him.

"No, you didn't neither of those deaths were your fault and Mavis was already dead. As for Zeref, well, he wanted to be put out of his suffering. It wasn't your fault, Natsu." She soothed.

"B-But-" He started but Erza cut him off sternly.

"I agree with Lucy, you couldn't control your curse. However what you did was reckless, leaving us with mere letters. Just how close to breaking were you anyway?" she asked at the end, concerned.

"A-Already gone." he muttered, shaking, causing Lucy to hug him tighter and glare at Erza. Erza flinched back, realising how unsensitive her question had been.

A quiet sore brought them back to the dragon slayer. It seemed the weeks of getting little to no sleep had caused him to fall asleep, making them all stare at the dark cirlces under his eyes.

Whatever he says later, Gray deserved to be chased around by Carla for using foul language in Wendy's presence.

Master Makarov himseld drove the Magical Vehicle back to Fairy Tail, back to their home. They laid the sleeping fire demon in one of the beds in the infirmary. They found out what he meant by 'nightmares' after he had several hours of rest.

The scream brought the guild rushing into the room, to see the most cheerful person, the childish dragon slayer, pale and thrashing around, features written into panic.

Happy eventually woke him up after several minutes of screaming with a bucket of cold water, but Natsu refused to talk about what he was dreaming about.

It wasn't until the fifth nightmare that he told Lucy and Happy, who had taken to keeping an eye on him, (their house was so much cleaner now) everything.

Happy came rushing to the guild to tell them the shortened version of events.

"Why isn't Lucy telling us this as well, if she was there too?" Gray asked once he recovered the ability to speak.

"She, erm... Is cheering Natsu up..." Happy stammered, he was clearly not supposed to mention this.

"Pray tell, what do you mean by that, Happy?" Mira asked, voice sickly sweet.

Unfortunatley the next day the whole guild knew about Natsu and Lucy's relationship and were paying up bets and swearing.

It took about a month for their Natsu to return. After the first damage bill, Makarov seemed reassured that everything was back to normal. Well, until he got the second one and discovered that Natsu still had his demonic powers and was very unhappy with anyone who hurt Lucy. Some things never change, some things change all the time. Fairy Tail was known for enduring, they always pulled through and they always will. It'd take a whole lot more than a curse to rip them apart.


	2. Moving forward

**A/N Hi guys, me again. Since you seemed to like this, I made another chapter. As usual, I don't own Fairy Tail or any of the characters. Hope you enjoy reading!**

Gildarts grinned as he looked out over Magnolia, glad to be back home after a long, challenging mission. He couldn't wait to relax in the guild and probably punch Natsu into a wall or something.

The usual alarm sounded as he marched towards the Guild Hall. He was welcomed back by cheers and yells, which only increased in volume when he reported his mission to be successful. He enthusiastically greeted his daughter, laughing as she pushed him away, blushing slightly from embarrassement. Still, all the life in the Guild was missing a certain something, or rather a certain someone.

"Where's Natsu?" he called to Makarov. Makarov thought for a moment before calling back.

"On a job with Lucy, Happy and Erza." he called cheerily.

"Why Erza?" Gildarts wondered. As far as he knew, Natsu was terrified of her, and Gray wasn't with them so that ruled out it being a team mission.

The Master looked saddened briefly, his expression became closed off. "She's the only one that can fight her way past his thrashing to wake him up from his nightmares."

"What?" Gildarts asked, blinking. Since when did Natsu have nightmares? What had he missed here, sure he loved going on long missions and all but he often missed big things that happened in his family.

After his exclaimation of shock, whispers travelled around the guild.

"He doesn't know."

"Darn, I forgot that he didn't."

"How on earth are we going to explain?"

"We can't leave it to Natsu, he's been through enough already."

"WILL SOMEONE JUST TELL ME WHAT'S GOING ON?" Gildarts bellowed.

...A couple of days before...

They took the train to the job, which made Natsu groan pathetically and curl up in a corner for the entire trip, earning a laugh from his three companions.

By the time they got to the town that was being terrorised by the dark guild, it was night so they decided to go to the hotel and destroy the guild in the morning.

Lucy and Erza watched Natsu anxiously, while Happy prepared a bucket of ice cold water. They were waiting for the screaming and thrashing that always happened whenever Natsu tried to sleep.

 _Natsu stood in a fancy hallway, staring, horrified at what lay before him. It was Future Lucy, the spear of shadows plunging into her chest, as always, his hand was too late, streched out, a inch away from the shadows as Future Lucy fell to the floor. Only this time, his Lucy wasn't there to catch her, all Future Lucy could do was stare at him, the life fading from her eyes, mouthing a word, the same word that he could never catch. He turned furiously to Future Rogue, snarling, but the man had already sent a wave of shadows at him, and suddenly he was drowning, the darkness tugging at his clothes, covering his eyes, he opened his mouth to scream..._

 _The darkness peeled away, light pouring in like he had just opened his eyes. He was waking up from his curse to see his brother limp on the end of his claws, blood blossoming from his chest as he smiled. His heart pounding, blood rushing in his head, but it couldn't quite cover up the thump of his brother falling to the floor, the tears in his eyes couldn't cover the image of his brother's hand limp on the grass._

 _Except it wasn't his brother anymore, but his father as he was buried by burning rubble, dragon looming in the sky and smoke heavy in the air. His brother's arms were around him, pulling him away, their mother rushing up to them, pushing them away, just as the dragon's sharp, gleaming black talons plucked her into the air. She let out a heartbreaking scream, telling them to run, but again, her last words were cut off as the dragon threw her into its open mouth, full of sharp, menacing fangs._

 _The dragon in the air changed, the image rippling as he gazed, horrified at Igneel's torn body, screaming as it fell, slowly, tears falling from his father's eyes. The voice in his mind fading. Being left... All alone. Alone._

 _Then he was on the cliff, looking back at his friends, fate behind him, casting its shadow over him, making sure he could never escape. Reaching for something he could never have, curse eating away at him as he used his last strength to say goodbyes, but he didn't get to go, the nightmare desire consumed him, his friends yelling for someone who wasn't there anymore._

 _"Nat-"_

 _"N-"_

 _"Natsu - up"_

 _"Wake up!"_

Ice cold water was chucked over the screaming dragon slayer, running down his face and mixing with his tears. He gasped for breath, his eyes darted around the room, taking in the faces around him, before slumping forwards, shoulders shaking with sobs.

"I-I'm sorry." he sniffed. "I'm only a-a burden now..."

Erza put a hand on his shoulder. "You know that isn't true, you're a very powerful mage and we care for you: you're no burden to us."

Lucy hugged him close. "Remember, you're here now, not where ever you were in those dreams, they happened a long time ago, we're all here now, we're all safe." she soothed.

"B-But-"

"Who was it this time?" she asked gentley.

"You, Zeref, my human mum and dad, Igneel and... I was back at the cliff, looking at you all as I felt myself losing against my curse." he choked between sobs. Lucy made a gesture with her hand, signalling for the others to give them some alone time.

In the morning they went to go and hunt down the dark guild. It was a S-Class mission but Erza assured them that they had nothing to worry about, the mages were nothing compared to what they faced before.

Still, the group was totally unprepared for the shockwave that came from behind, knocking them to the floor, only for an earth mage to send stones flying at them. Natsu watched, eyes wide with horror as his friends cried out in pain.

 _Natsu, don't worry, we're here for you!_

 _We don't care if you're a demon._

 _I love you!_

He clenched his fists. _I'm not going to let them suffer, not after they did so much for me, not after they accepted me for who I was and helped me fight away my past. How dare this pathetic dark guild hurt them._

His eyes narrowed, demonic powers brought to the surface by his fury, claws appearing on his hands. He wasn't afraid anymore. He was done running. He would protect his friends.

His voice came out as a snarl as he stood up, making the dark guild members cower. "Don't you dare make another move."

His claws lit up with a wild gold fire, his eyes gleamed. He rushed forwards, his wings snapped out letting him get up close to them, giving each of them several punches, knocking them out. The last thing they heard before falling unconscious was Natsu's cold tone.

"Come near them again and I _will_ kill you."

His demon form vanished, and he turned back to his friends, who were shakily standing up.

"Are you guys okay?" he asked, voice softening.

"Yeah, thanks for that Natsu." Erza answered for the group.

"Wah, Natsu, your eye! It's gone red, like your demon form." Happy cried, rushing in to get a better look.

Erza and Lucy limped over to see as well. "It looks pretty." Lucy complimented. "How long do you think it'll last?" she asked.

Natsu shrugged. "Heck if I know, probably a week."

The team burst out laughing and started walking home.

They got back to the guild just as the brawl over who would have to tell Gildarts finished.

"We're back!" Happy yelled, flying into the guild, only to cause everyone to stare at the group.

"What's going on?" Erza's gaze darkened. "Have you all been fighting?" she snarled, causing everyone to shiver.

"N-No, of course not Erza, we were erm... Guys help!" Gray stammered.

"Relax Erza," the Master laughed. "How was the mission?"

"It was a success, Natsu defeated them all in about thirty seconds, we were all knocked to the floor and unfortunatley unable to help, he used his new powers." she summed up, sitting down.

"That explains why it was over so quickly. Did he have any nightmares?" Master asked, now having to talk over the usual chatter of the guild.

"I'm right here you know." Natsu interrupted. Lucy sighed, shaking her head, then hid behind Natsu to avoid a table that had been sent flying from whatever fight was going on.

"Oh, hi- Holy! Natsu, your eye!" He exclaimed.

"Yeah, I know." He muttered.

Gildarts had recovered from the shock of not being instantly challenged to a fight and walked over to them.

"Hey kiddo." he smiled as he ruffled Natsu's hair. Natsu turned to beam back at him.

"Hey pops!"

"What? Your eye- it's red." he yelled.

"This is so much more trouble than it's worth." Natsu grumbled, slapping a hand over his eye.

"Seriously kiddo, what happened?" Guildarts questioned.

"It's a really long story, if you want to hear everything." Natsu said, avoiding Gildart's eyes.

"And if he's going to tell it, I'm going to be right there next to him." Lucy stated, eyes serious.

Unsuprisingly, the quietest place they could find was the infirmary. Lucy held Natsu's hand while he was speaking, which made Gildarts raise an eyebrow.

"Well, to understand everything, we need to start from right after you left, when we took part in the Grand Magic Games."

"Oh yeah, I heard about that."

"Well, erm. When I fought Sting and Rogue I shoved Gajeel into a minecart and he found a mass grave of dragons. Long story short we discovered a time travelling gate that some people from the future came through. One was Luce and the other was Rogue, who brought dragons through and attacked the city. We fought them off but he killed Future Lucy, she died in her own arms and I... I wasn't strong enough to save her."

"You shouldn't blame yourself, no one saw it coming, none of us could've stopped it."

"Thanks Luce, erm... What was the place where we found Atlas Flame again?"

"Idiot, the Sun Village."

"Oh yeah, thanks. So we got a job request from Mr. Tree Guy and went to a village to get rid of some ice, which covered the whole village thanks to an ice devil slayer. We then learned of E.N.D, a demon created by Zeref and the master of the dark guild Tartaros."

"Natsu, he was called Warrod, and he was one of the founders of the guild."

"Oops, my bad."

"A guild of demons... Sounds creepy."

"Anyway, a while later, the demons started attacking former council members so we decided to go and protect them. Erm, who was it again that was the traitor? Nevermind, one of them sold out Mira and Erza to the guild so we went to save them. I think we all lost a lot while fighting the demons and it eventually got down to Gray and I against the Underworld King Mard Geer. At some point in the fight, the book containing the demon E.N.D opened and-"

"Wait what? The book opened and Zeref's strongest demon appeared. That has to be at least as strong as Acnologia and none of you got a life changing injury?" Gildarts yelled.

Natsu sighed. "Etherious Natsu Dragneel."

Gildarts blinked. "What?"

"E.N.D stands for Etherious Natsu Dragneel. When the book opened I regained my memories and powers... A-And my... My curse."

Gildarts looked confused. "A curse? You're a demon. What?"

Lucy face palmed. "For the love of... Were you even listening?"

Gildarts laughed and waved a hand airily. "Yeah, yeah, just messing with you. What kind of curse?"

Natsu looked at his hands, imagining claws covered in blood. "One that made me want nothing more than to kill Zeref."

Gildarts looked up at him sharply. "What happened then?"

"What? With the curse or after the battle."

"Erm, go with after the battle."

"Igneel d-died." Natsu furiously rubbed his eyes, determined not cry.

Gildarts crushed the boy in a hug, holding him tight.

Eventually they broke apart and Gildarts gave him a tight smile. "Okay Kiddo, what happened next?"

"You know those two months I fought the curse off? Well, it actually affected me from the first week so the rest was a living hell."

Lucy gasped. In the first week, he had been comforting her about Aquarius. The more she thought about it, the more it seemed like something Natsu would do, brush his own pain away in order to help someone else. Gildarts raised an eyebrow at Natsu's expression.

"Headaches, nightmares, a constant tugging in my gut. It went to physical pain in the third week. It sucked."

The silence hung heavy in the air. Gildarts asked tensley. "Did you kill Zeref in the end?"

Natsu laughed mirthlessly. "Yeah, I had to in the end. It was pathetic, I only lasted two months. I went there, knowing that if I killed him, I would dissapear as well, but I couldn't fight it. I honestly thought I was going to die, until Fairy Tail showed up. They just about pulled me back, I was about to go with them, away from the fate, thinking I could fight it off but... I lost control and when I regained my senses my brother was limp on the end of my claws."

Natsu couldn't go on after that, he couldn't bring himself to say what happened next. They didn't need to know. _That when I was vanishing into the light, I was relieved, I could feel the weight of the curse releasing my soul. That as selfish as it was I wanted so badly to stay but at the same time, I felt free, nothing else dragging me down: I'd finally be free of my past._

Lucy saw the tears glistening in his red eye, and decided to put a stop to this before Natsu ended up hurting himself more.

However, before she could have moved, Gildarts spoke. "Hey Kid, how strong is this new form of yours? I challenge you to a fight, to find out. Who knows, you might finally beat me."

Natsu looked deep in thought, and expression that he didn't normally wear. "Fine. Give me two days to prepare then I'll fight you."

He then grabbed Lucy's hand and ran out of the room.

The second they were out of sight and in the woods Natsu summoned his demon wings and flew at top speed, carrying Lucy in his arms. She didn't ask any questions, she just watched the trees blur.

They eventually landed in a clearing.

"Hey Luce, can you help me with something." he asked seriously, looking in the eye. The effect of one dark eye and one deep crimson was slightly unnerving, but Lucy didn't care.

"Sure, you can trust me with anything." she murmured, gripping his handhand tightly.

"I'm going to have to use my demon form and there's something there that makes me want to win with, well, a burning desire, a stronger form of the curse. Since I was made to be a demon capable of causing mass destruction and killing Zeref, it wouldn't do for me to give up and lose. I probably won't last long against that. So if both of my eyes go black, I'll need you to stop me."

Lucy couldn't belive her ears. "Natsu, why are you doing this to yourself, you never have to use that form again."

He sighed, smiling bitterly. " If I don't, I'll always be scared of it and that'll give it power over me. I have to get over it somehow."

"Natsu..."

"Anyway, Luce, I'll need your help. If I do lose control, I need you to pull me back."

"If you lose it, won't you kill anyone who gets in your way?"

To her suprise, his grin widened. "Do you honestly think that I'd ask you that without a plan?"

He grabbed her hand and traced a mark, which flared up a second later. There was a black flame symbol, nearly identical to the ones he had in his demon form.

"With this, no matter who far gone I am, I'll recognise you and erm... Protect you." Natsu blushed at the end, which made Lucy strongly suspect it was something else.

"What does it really do?" she asked, raising an eyebrow suspiciously.

"Eh, makes me remember I love you and that kind of stuff."

Lucy blushed, taking Natsu's hand. He grinned and squeezed her hand, fingers brushing her new mark.

Gildarts stood facing Natsu in the middle of a forest. "Well, you going to give me a good fight or what?" he taunted.

"Hell yeah!" Natsu yelled, charging forwards, hand covered in a dazzling flame. "Fire Dragon's Iron Fist!"

Gildarts chaught it easily and looked at Natsu, unimpressed. "Really, you should know by now that a spell like that won't work."

Natsu didn't laugh with him but merley muttered. "Worth a shot. Sorry, Igneel."

By now, quiet a crowd had gathered, egar to see Natsu's new form for themselves, or wanting to see the outcome of this fight.

Natsu's body glowed with a crimson light before as a pink blur he leapt at Gilarts, claws curled into fists. Gildarts was still taking in Natsu's new form and didn't see the punch coming. Gildarts winced and clutched his arm, only to fling his hand away as the mark started to glow with heat.

Natsu didn't stop, leaping away from the burst of Gildart's crash magic and continuing to send a flurry of punches to the man's face. Gildarts grunted and caught his hand and sent Natsu flying into a tree.

Natsu snarled and launched back at Gildarts, one of his eyes turning black, red pupil flashing with rage. It was terrifying but Gildarts didn't seem scared, instead he merley picked up the pace of his attacks, laughing.

Natsu was still in control. He knew that if Gildarts got any more powerful things would become dangerous but he was okay for the moment. Everything was going okay, he still had a lot of power left. That was until one of Gildart's attacks missed and shot towards the crowds, who scrambled but somehow, amongst all the pushing, Lucy was left behind.

The magic hit her full force and she was tossed through the air, crying out. Natsu's vision snapped into focus. Before he knew what he was doing he had caught Lucy and gently lowered her to the ground, every whimper of pain causing his blood to simmer with rage.

Gildarts felt terrible. He didn't mean for his attack to get out of control and hurt people like that, and although he didn't know Lucy very well, she seemed very nice and was someone important to Natsu.

Natsu had turned to face him after he set Lucy down a safe distance away. Something seemed wrong, something in the air, tense and amost silent. Almost like he was in a trance, Natsu lifed a claw and slashed his arm. Gildarts stared in a mix of shock and horror as fire and blood sprayed from the wound. Something seemed to happen, there was a brighter flash.

The markings were gone, as were all his demonic features. There was one simple mark on his arm: **E.N.D**. There were only two other differences from their usual cheerful Salamander. His veins glowed slightly, as if there was fire running through them. That and his eyes. They were back to their usual colour but they were horrible. Something terrible and ancient glowed in them, some horrific long forgotten power.

"You." He snarled, turning those terrible eyes on him. "Hurt. Lucy."

For the first time since Acnologia fought him, Gildarts felt fear. Whatever this was, it wasn't Natsu, not anymore. He'd clearly lost control of his new powers. Fissures broke the ground and golden flames poured into the air. leapt towards him, face a mask of fury. Gildarts tried in vain to stop his first attack but was sent flying backwards. There was unbelievable force behind the attack. He struggled to get up from the rock pile, all too aware of the monster getting closer.

"N-Natsu... Stop, please." Lucy coughed, making the demon freeze.

"No. He hurt you."

"This isn't you, I know you're in there somewhere. You'd never hurt your family... Not like this."

The monster didn't move but slowly turned to face Lucy, Gildarts could only just see his face if he strained and was suprised to see that the demon was crying and one of its eyes was Natsu's.

"I-I'm sorry." It choked, falling to its knees.

"Ice Make: Cage!" Gray roared, bursting into the clearing and using his ice devil magic to contain it.

"No, stop, that's Natsu. Why are you putting him in a cage?" Lucy cried limping forwards.

"Lucy, look what he did to you and Gildarts." Gray exclaimed.

"What happened to me was an accident and Gildarts did it. Natsu only lost control because I got hurt."

Gray raised an eyebrow and released Natsu, but made ice chains around his ankles and wrists.

"Why?" Lucy asked, voice sad and hoarse from the screaming.

"Look, do you think I want to do this either, but what if he wakes up and tries to kill us all again?" Gray snarled, trailing of at the end, wiping away a tear.

His magic reacted with his temper and flipped Natsu over. Gildarts, who had limped over stared in horror at Natsu's face. The Dragon Slayer wasn't knocked out like they thought he was but was silently crying.

"I'm sorry, I never even thought that I'd ever use that form again..." he choked, looking away from them.

"What was that?" Gildarts asked, though his voice wasn't hostile. In fact he sounded impressed.

"Well, I am Zeref's strongest demon and that was E.N.D's true form, although I was only ever able to use it if Zeref got out of control. I guess seeing Lucy get hurt somehow triggered it." he muttered, looking away from them.

"You said again, what happened the last time?" Gray asked curiously.

"I was alone and I ran into the dragon who killed my human parents. It was a death dragon and he merley laughed when I challenged him. I was furious and I somehow unlocked it, I only saw the dragon who killed my parents and I used that form. I ripped the head from his shoulders in one movement. I fainted for about a week and Zeref and Igneel panicked and looked everywhere for me, eventually they found me, pale and lifeless. They were terrified and sealed the form deep inside me, only something horrible would bring it to the surface."

"What caused it this time?" Gildarts asked.

 _"I'll protect the future, I promise."_

 _"No one is gonna steal Lucy's future."_

 _"Natsu, look, I got my Fairy Tail guild mark!"_

 _"I believe in you Natsu, I have ever since I joined the guild."_

 _"You came back to me. Thank you Natsu."_

He started at the floor. "I have an idea."

Nobody pushed it any further, instead they all limped back to the guildhall. All their troubles seemed to vanish as they winced in harmony to Porlyusica's scolding. Everything seemed to go back to normal. Well, Natsu was promoted to S Class, which caused a party, a brawl and a furious Gray, Gajeel and Elfman. Well, that last one was to be expected, they all wanted to get to S Class. Looks like Natsu won that little competition, and now they were all training extra hard in order to be the next one to become S Class. Poor Master Makarov was getting a lot more damage bills now. As for Gildarts? He just laughed at how much paperwork Makarov had to do.

Natsu still had nightmares but Lucy was always there to calm him down. As long as they stuck together, they would get through anything. It was their nature, to survive, no matter how dark the world looked, for each other, for their family.


End file.
